By 2011 there were 180 known super-Jupiters, some hot, some cold.[2] Even though they are more massive than Jupiter, they remain about the same size as Jupiter up to 80 Jupiter masses.[2] This means that their surface gravity and density goes up proportionally with their mass.[2] The increased mass compresses the planet due to gravity, thus keeping it from being larger.[2] In comparison, somewhat lighter planets than Jupiter can be larger, so-called "puffy planets" (gas giants with a large diameter but low density).[3] An example of this may be the exoplanet HAT-P-1b with about half the mass of Jupiter but about 1.38 times larger diameter.[3]

Corot-3b, with a mass around 22 Jupiter masses,[4] is predicted to have an average density of 26.4 g/cm3, greater than osmium (22.6 g/cm3), the densest natural element under standard conditions. Extreme compression of matter inside it causes the high density, because it is likely composed mainly of hydrogen.[5] The surface gravity is also high, over 50 times that of Earth.[4]